Field of the Invention: Gas valve assemblies having diaphragm actuators with pressure regulators for maintaining the outlet pressure at some predetermined value have continually been faced with the problem of a compromise between good control and fast operation on an initial opening of the valve to have sufficient gas flow for ignition. In order to be able to use a main valve with a small stroke for control as sensitive as possible, the servo feed orifice should be small in order that the gas supply to one side of the diaphragm remains small and the venting from the other side of the diaphragm is possible with small movement of the servo valve. On the other hand, there is a requirement that the outlet gas pressure be sufficient for ignition of the burner and must be established within predetermined limits of time, for example, within two or three seconds, which means a sufficient pressure for actuating the main valve means must be reached on one side of the diaphragm in this time interval. The diaphragm chamber comprises a certain volume by reason that the diaphragm diameter and the stroke necessary for actuating the main valve. This diameter need be large when the gas valve is of a certain security class and must overcome a strong spring acting upon the main valve. The requirement of a small feed orifice is a necessity and yet for the initial opening of the valve, such can be a fatal limitation.